#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>

int main()
{
    int n = 0, h = 0, m = 0;
    scanf("%d %d %d", &n, &h, &m);
    if (m <= n * h)
        n = n - (m / h) - (m % h);
    printf("%d", n);
    return 0;
}